convertimate Metal hardness (HRC, HB, HV)

Rockwell C to tensile strength in ksi (approx.)

Type a value in HRC to get it in ksi instantly.

185.6ksi

That's 1.96× as hard as 304 stainless steel, while spring steel is 1.14× harder.

What it means

How hard is that?

For carbon and alloy steels (ASTM E140). Conversions between scales are approximate; for other metals and for exact values, test on the scale you need.

The math

How to convert HRC to ksi

Hardness scales convert by table (ASTM E140): HRC 50 = 513 HV = 481 HB, HRC 40 = 392 HV = 371 HB. Tensile strength ≈ 3.45 × HB MPa.

Example: 40 HRC = 185.641 ksi.

Every unit

That hardness on every scale

Tables

HRC to ksi conversion table

HRC to ksi conversion table
HRCksi
20 HRC113.086 ksi
25 HRC126.596 ksi
30 HRC143.109 ksi
35 HRC163.624 ksi
40 HRC185.641 ksi
45 HRC210.66 ksi
50 HRC240.683 ksi
55 HRC280.213 ksi
ksi to HRC conversion table
ksi to HRC conversion table
ksiHRC
127 ksi25.1 HRC
143 ksi30 HRC
164 ksi35.1 HRC
186 ksi40.1 HRC
211 ksi45.1 HRC
241 ksi50 HRC
280 ksi55 HRC

Quick answers

Quick answers

How many ksi is 40 HRC?
40 HRC is 185.641 ksi.

The units

About these units

Rockwell C (HRC)

Rockwell C: depth under a diamond cone, for hardened steel (20–68).

Tensile strength in ksi (approx.) (ksi)

Estimated ultimate tensile strength of steel, in thousands of psi.

Learn more about hardness units

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